Automatic laundry cleaning and drying is done by washing machines and dryers. These machines are a well known part of life, and the majority of dwellings in the USA have such machines nearby. It is well known that part of their operating cycle involves spinning and tumbling. Spinning, as the term suggests, revolves the basket or drum containing the clothes at a high speed to employ centrifugal force to extract the water from the clothing. Tumbling revolves the clothing containing drum at a slower speed to allow the clothing to fall and cascade through the hot air flow of the drying machine. Both of these operations cause unbalanced forces to be transmitted to the outer framework of the machines. In the case of the spinning of the washing machine, the vibration can cause an alarming and disturbing noise and even make the entire machine move, or “walk”, from its installed position.
Machine designers have attempted to arrange for absorption and/or counteraction of these unbalanced forces both internally and externally in an effort to mitigate the obvious problem. External absorption devices are employed in the mounting feet of the machine. Several designs are used and usually involve a rubber pad in contact with the floor. As the floor is not perfectly flat, it is a common practice to use four feet, with at least one foot being adjustable so that all four feet equally support the weight of the machine. Most current designs of the adjustable feet use the simple idea of having an internal thread rigidly fixed to the base of the machine and a mating externally threaded stem with a rubber pad contained in a cup at one end of the threaded stem.
When the machine is installed and located in its final position, the levelness and the equality of support between the four feet is established by turning the adjustable stem. In practice, there are two problems which arise, both of which can lead to destruction of the foot's essential vibration-absorbing rubber pad. First, during installation, the machines are dragged and pushed across a floor. The floor can be tiled, linoleum, steel, plain rough concrete or any other floor material which might be at the installation site. The weight of the machine and the friction between the rubber pad and the floor determine the transverse load felt by the entire foot assembly. This load can be high enough to bend the foot assembly and even if that extreme is not reached, it can be high enough to abrade the rubber and/or cause it to split and be destroyed to the extent that it cannot perform its function.
Second, after installation, it is necessary to adjust the feet, and in turning the adjustable feet the rubber is forced to turn against the high pressure and friction between the rubber surface and the floor. This puts extreme stress on the rubber features which serve to retain the rubber in its cup. If these features fail and crumble, then upon subsequent movement of the machine, say to another location or simply for repair, the rubber can fall out, and the machine loses its ability to be easily leveled. Thus there is a need for a device which solves the aforementioned problems.
Moreover, it often happens that owners of a laundry machine do not adjust the adjustable feet prior to installation, and/or simply try to level the machine to reduce vibration using a shim of some kind, such as cardboard or the like. The laundry machine owner may not make the proper adjustment because they do not know the feet can be adjusted or because the feet may be difficult to adjust once the machine is set up. Often it is the case the proper tool is not available to make the adjustment. Thus there is a need for a device to snub out the vibration, without requiring tools.